Microcystin Synthetase
Mostrando 1-12 de 14 artigos, teses e dissertações.
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1. Phenotypic, genetic and bioactivity analyses of Brazilian cyanobacterial isolates from the genera Fischerella and Hapalosiphon / Análise fenotípica, genética e de bioatividade de isolados brasileiros de cianobactérias dos gêneros Fischerella e Hapalosiphon
A afiliação genérica de Fischerella e Hapalosiphon é problemática devido à instabilidade dos caracteres morfológicos. Os gêneros Fischerella e Hapalosiphon são diferenciados pela presença de tricoma multisseriado e uni ou bisseriado, respectivamente. Porém, geneticamente esses caracteres não se mostraram diacríticos para diferenciar gêneros. Es
Publicado em: 2009
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2. Implementation of Real Time Quantitative PCR technique (qPCR) for the monitoring of Microcystis and potentially microcystin-producing genotypes / Implementação da técnica de PCR Quantitativa em Tempo Real (qPCR) para o monitoramento de Microcystis e genótipos potencialmente produtores de microcistinas
Florações de cianobactérias tóxicas em corpos dágua doce usados como fonte para o consumo humano, recreação e irrigação são freqüentes nos dias de hoje devido à eutrofização destes ambientes. O monitoramento de linhagens tóxicas é importante para a prevenção dos efeitos adversos causados por suas toxinas na saúde de humanos e animais. Mét
Publicado em: 2008
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3. Phylogenetic evidence for the early evolution of microcystin synthesis
Cyanobacteria are a prolific source of secondary metabolites, including compounds with toxic and enzyme-inhibiting activities. Microcystins and nodularins are the end products of a secondary metabolic pathway comprised of mixed polyketide synthases and nonribosomal peptide synthetases. Both peptides are potent natural toxins produced by distantly related gen
National Academy of Sciences.
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4. Quantitative Real-Time PCR for Determination of Microcystin Synthetase E Copy Numbers for Microcystis and Anabaena in Lakes
Cyanobacterial mass occurrences in freshwater lakes are generally formed by Anabaena, Microcystis, and Planktothrix, which may produce cyclic heptapeptide hepatotoxins, microcystins. Thus far, identification of the most potent microcystin producer in a lake has not been possible due to a lack of quantitative methods. The aim of this study was to identify the
American Society for Microbiology.
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5. Light and the Transcriptional Response of the Microcystin Biosynthesis Gene Cluster
Microcystin, a hepatotoxin known to be the cause of animal and human deaths, is produced by the bloom-forming cyanobacterium Microcystis aeruginosa in freshwater bodies worldwide. The toxin is produced nonribosomally via a multifunctional enzyme complex, consisting of both peptide synthetase and polyketide synthase modules coded for by the mcy gene cluster.
American Society for Microbiology.
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6. Natural Variation in the Microcystin Synthetase Operon mcyABC and Impact on Microcystin Production in Microcystis Strains
Toxic Microcystis strains often produce several isoforms of the cyclic hepatotoxin microcystin, and more than 65 isoforms are known. This has been attributed to relaxed substrate specificity of the adenylation domain. Our results show that in addition to this, variability is also caused by genetic variation in the microcystin synthetase genes. Genetic charac
American Society for Microbiology.
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7. Microcystin Biosynthesis in Planktothrix: Genes, Evolution, and Manipulation
Microcystins represent an extraordinarily large family of cyclic heptapeptide toxins that are nonribosomally synthesized by various cyanobacteria. Microcystins specifically inhibit the eukaryotic protein phosphatases 1 and 2A. Their outstanding variability makes them particularly useful for studies on the evolution of structure-function relationships in pept
American Society for Microbiology.
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8. Genes Coding for Hepatotoxic Heptapeptides (Microcystins) in the Cyanobacterium Anabaena Strain 90
The cluster of microcystin synthetase genes from Anabaena strain 90 was sequenced and characterized. The total size of the region is 55.4 kb, and the genes are organized in three putative operons. The first operon (mcyA-mcyB-mcyC) is transcribed in the opposite direction from the second operon (mcyG-mcyD-mcyJ-mcyE-mcyF-mcyI) and the third operon (mcyH). The
American Society for Microbiology.
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9. Multiple Alternate Transcripts Direct the Biosynthesis of Microcystin, a Cyanobacterial
The mcyABCDEFGHIJ gene cluster of Microcystis aeruginosa encodes the mixed polyketide synthase/nonribosomal peptide synthetase (microcystin synthetase) which is responsible for biosynthesis of the potent liver toxin microcystin. The sequence and orientation of the mcy genes have previously been reported, but no transcriptional analysis had been performed pri
American Society for Microbiology.
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10. Characterization of the Nodularin Synthetase Gene Cluster and Proposed Theory of the Evolution of Cyanobacterial Hepatotoxins
Nodularia spumigena is a bloom-forming cyanobacterium which produces the hepatotoxin nodularin. The complete gene cluster encoding the enzymatic machinery required for the biosynthesis of nodularin in N. spumigena strain NSOR10 was sequenced and characterized. The 48-kb gene cluster consists of nine open reading frames (ORFs), ndaA to ndaI, which are transcr
American Society for Microbiology.
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11. Inactivation of an ABC Transporter Gene, mcyH, Results in Loss of Microcystin Production in the Cyanobacterium Microcystis aeruginosa PCC 7806
The cyanobacterium Microcystis aeruginosa is widely known for its production of the potent hepatotoxin microcystin. Microcystin is synthesized nonribosomally by the thiotemplate function of a large, modular enzyme complex encoded within the 55-kb microcystin synthetase (mcy) gene cluster. Also encoded within the mcy gene cluster is a putative ATP binding cas
American Society for Microbiology.
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12. Detection of Toxigenicity by a Probe for the Microcystin Synthetase A Gene (mcyA) of the Cyanobacterial Genus Microcystis: Comparison of Toxicities with 16S rRNA and Phycocyanin Operon (Phycocyanin Intergenic Spacer) Phylogenies
The relationship between toxigenicity and phylogeny within the cyanobacterial genus Microcystis is unclear. To investigate this issue, we have designed PCR primers for the N-methyltransferase (NMT) domain of the microcystin synthetase gene mcyA and have probed 37 Microcystis sp. cultures as well as several field samples. The NMT region was present in all 18
American Society for Microbiology.